The present invention relates to a novel construction of a magnetic head assembly having a recording/reproducing magnetic head and erasing magnetic head for limiting the recording width of the recording/reproducing magnetic head. More particularly, the invention is concerned with a novel magnetic head assembly of the type mentioned above, making use of a ferrite material of Mn-Zn system as the material of the cores of the magnetic heads.
As a measure for enhancing the magnetic recording density, it has been proposed to reduce the width of the recording track. This, however, requires a thinning of the cores, which in turn imposes various problems. Particularly, in the magnetic head assembly having a complicated construction in which the recording/reproducing magnetic head and the erasing head are incorporated in a common case, the thinning of the cores leads to serious problems such as stringent requirements for dimensional precision in the assembling of the head assembly and breakdown of the cores themselves.
Recently, in order to obviate the above-described problems of the prior art, a magnetic head assembly has been proposed and put into practical use, in which reinforcers of a non-magnetic material are bonded to the recording/reproducing magnetic head cores and the erasing magnetic head cores thereby to rigidly reinforce and stiffen these cores while enhancing the precision of distance between the recording/reproducing magnetic head and the erasing head. This type of magnetic head assembly is disclosed, for example, in Japanese Patent Publication Nos. 810/1980 and 31763/1978 (U.S. Pat. No. 3,846,840), Japanese Patent Laid-open Nos. 143217/1979 and 22816/1979 (U.S. Pat. No. 4,110,804) and Japanese Utility Model Laid-open No. 26915/1979. The magnetic head assembly of this type now actually used, however, has inferior electromagnetic conversion characteristics and does not fully meet the requirements for performance, because the cores of the magnetic heads are made from a ferrite material of Ni-Zn system. This created a demand for development of magnetic head assembly making use of a ferrite of Mn-Zn system having a higher performance as the material of the magnetic head cores. Unfortunately, however, such a magnetic head has not been put into practical use because of cracking in the glass bonding between a reinforcement member of a non-magnetic ceramic material and the core of a ferrite of Mn-Zn system for reinforcing the latter.